Apparatus for treating slimes in ore reduction.



APPLICA ION FILED APR. 27.1904. RENEWED MAB. 30,1905.

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N0."796,503. PATENTED AUG. 8, 1905. G. A. DUNCAN.

APPARATUS FOR TREATING SLIMES IN ORE REDUGTION.

APPLIGATION FILED APR. 27. 1904. RENEWED MAR. 30.1905.

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U ITED STATES PATENT OFFICE.

APPARATUS FOR TREATING SLIMES IN ORE REDUCTION.

Specification of Letters Patent.

Patented Aug. 8, 1905.

Application filed April 27, 1904. Renewed March '30, 1905. Serial No. 252,919.

- metal values from slimes, adapted to be employed in the process described in my divisional application hereof, Serial No. 215,17 3, filed July 2, 1904. i

It consists of the features of construction of the apparatus set out in the claims.

In the drawings, Figure l is a plan view of an apparatus for practicing my invention. Fig. 2 is a vertical section at the line 2 2on Fig. 1. Fig. 3 isa horizontal section at the line 3 3 on Fig. 2. Fig. 4 is a detail view of the bottom gates, showing a modified structure. Fig. 5 is a section at the line 5 5 on Fig. 3. Fig. 6 is a section at the line 6 6 on Fig. 3.

In practicing my invention I employ one or more tanks or vats A, in each of which there is suspended a filtering-cell B, which is only enough less in horizontal dimensions than the tank in which it is suspended to leave room for the accumulation upon its lateral surfaces of a predetermined thickness of slimes and enough additional space outside the same when so accumulated for the necessary circulation of the liquor or cleansing-water at the different stages of the process hereinafter described. The construction of the cell may be substantially such as shown in a pending application of Oliver P. Ankeny, Serial N 0. 198,076, filed March 14, 1904, in which there is employed a frame or stretcher 1, over which there is drawn a filtering bag or sack 2, which is held sufliciently spread to insure free movement of liquid through it by means of spacing-ribs 4 4 4, &c., onto which the bag or sack is bound by exterior clamps 5 5 5, to prevent the walls of the cells from spreading unduly in any mode of use requiring interior pressure. The cell-frames have their side bars widened at the upper ends for a short distance from the top, as seen at 6 6, to afford better opportunity for securing the top bar and making the connections hereinafter explained. When a plurality of tanks and cells are used in one apparatus, all the tanks may be constructed integrally as compartments in a continuous structure, and they are so represented in the drawings. Each tank or compartment has a depth enough greater than the'height of the filtering-cell to permit the latter to depend into it to the full extent of the surface on which deposit is desired without reaching the bottom so as to rest thereon, several inches being preferably left between the bottom of the filtering-cell and the bottom of the tank for the purpose of agitation of the liquid contents of the tank and drainage and flushing, as hereinafter explained. In each of the cells there are any desired number of pipes C O C, connected to a pumping apparatus (conventionally represented at D) for sucking the liquid in the tank and in which the cells are immersed through the filtering-walls of the cells to cause the deposit of solids upon the outer walls of the latter. These pipes for this purpose extend from the top down to a point near the bottom of the cells, where they open totake in theliquid. Theliquid shown in the tank in Fig. 2 may be understood to be slimebearing liquid, the slime being supposedly charged with metal values which it is the purpose of the process to extract and the liquid being also charged with a proper metal-solvent liquor adapted to the mineral character of the slimes. Pipes E EE, extending longitudinally under the bottom of each tank, have their outer curved surface only partly exposed and are perforated at thelower sides for discharge of air at a multiplicity of points into the liquid in the tanks to keep the same agitated and cause the slimes to remain in suspension. to be connected with any source of air (not shown) by which the air-discharge is maintained, as described. The slime-bearing liquid is supplied continuously at the top of the tank, as indicated by the pipes F, extending along the top of the tanks and discharging into them at frequent intervals, (indicated by the discharge-nipples F F,) the supply being made adequate to make good the drainage effected by suction through the filtering-walls of the cells and carried off by the pipes 0 until the desired thickness of deposit of slime is produced upon the outer walls of the cells. Thereupon the supply of slime-bearing liquid being cut off thesuction will be continued through the pipes C until the liquid is substantially exhausted from the tank down to the bottom of the cell, the air-supply through These pipes may be understood the pipes E being reduced, if necessary, as the level of the liquid falls, so as not to produce undue agitation in the reduced quantity. A fresh metal-solvent liquor adapted to attack and take up the metal values still contained in the slimes will now be introduced into the tank either through the pipes E or if by reason of the smallness of their discharge-apertures this method is too slow then through similar pipes G, having freer discharge at frequentintervals, (indicated by the apertures g, for example,) and the tank being kept filled with such solvent liquor,suction being applied, as before, through the pipes C, such solvent liquor will be sucked in through the slimes deposited on the cells and will dissolve out the metal values in the latter, and the discharge from the pumps being collected may be treated in the customary manner for recovery of metal values from the liquor thus drawn through the slimes. After this step in the operation has been continued for a sufficient length of time to extract the metal from the slimes to such degree as may be economically effected in this manner the metal-solvent liqnor will be withdrawn by cutting 01f the supply and continuing the suction until the tank is empty or by directly draining the tank through the bottom, if preferred, and asupply of clear water will be furnished through the pipes E or G. The tank being filledwith water to the top of the cells and the suction continued, the remainder of metal-solvent liquor with whatever metal values it may carry will be washed out of the slimes and collected for further treatment. After the slimes have been thus thoroughly washed out, so that not only all the metal values possible, but all the solvent liquor worth recovering have been washed out, the slimes may be detached from the outer surface of the cells by any convenient means. A satisfactory means consistsin reversing the pressure so that water is forced into instead of drawn out of the cells and by the pressure from within operating outward through the canvas forces the accumulated load of slimes off from the latter, so that being detached it falls bodily into the tank and can be carried away through the dischargepassages upon opening the same and flushing out the tank with clear water. This process also tends to clear the interstices of the canvas, leaving it in proper condition for repetition of the filtering action when suction is again applied as at first. It is desirable also to flush off the outer surface of the canvas and assist the action of the interior pressure in detaching the slimes, and this is accomplished by means of water-jets directed against the outer surface of the cells at the top of the slime deposit, which is thus attacked in position to leave no marginal residuum adhering to the canvas. For this step of the process I provide a horizontal pipe J, extending along each side of each cell at the top, with discharge apertures or nozzles for directing a multiplicity of jets of water inward and downward against the sides of the cells. A valve K controls this entire system of flushing-pipes. With slimes of certain character the exterior flushing alone maybe adequate for detaching the residuum and washing the outer surface, and in other instances the character of the slimes may be such that the interior pressure alone will detach them cleanly; but in most cases it is desirable to employ the two expe dients cooperatively, as described. In the drawings there is shown means for producing the suction and pressure only in conventional manner without regard to structural details. Any familiar means for producing these effects may be employed. In the drawings it may be understood that the pump D operates to withdraw the liquid from and through the cells, as described, and that the pipe M is connected with a source of water under pressure for operating in the opposite direction when the valve M is opened and the pump is not in operation. The water supplied through the pipe M for flushing the slimes, as above described, serves also to assist in flushing out the tank and delivering the residual mud therefrom.

For the purpose of conveniently emptying the tank and flushing it the bottom is formed of trap-doors or gates N N N, which are hinged at one lateral edge to a frame secured to the side and end walls at the bottom and reinforcing the structure, suitablepacking (represented at P) being provided on the lower side of said frame, against which the trapdoors or gates N seat when closed, any convenient means being provided for clamping said trap-doors or gates tightly upward against the bottom of the tank to prevent leakage. As illustrated, this is done by the bolts 0. rooted in the frame 0 and taking through slotted slugs N N on the trap-doors or gates, N, and having nuts n 72 below the lugs, the pivot-line of the hinges of the gates being so located as to require a little compression of the packing at the hinged side-of the gate in order that the opposite side may come to its seat, thus insuring proper compression of the packing all around.

In order that the pipes E may be used both for discharging air and also for discharging, first, the metal-solvent liquor, and, second, the clear water, as described, they may be provided with a four-way connection E one branch of which leads to the pipes E, the other three having, respectively, valve connections E, E*, and E for admitting the air, the metalsolvent liquor,and the water in turn. The pipe Gr when employed may be similarly provided, except that it will not require the air connection.

Instead of the bolt-fastenings for the bottom gates N a more quickly operated device may be provided, which is shown in Fig. 4,.

consisting of alink T, pivoted to a lug T, projecting from the bottom of the frame 0, the link having on its lower bar an eccentric T and space above the eccentric for the entrance of a lug or nose N of the gate N and the eccentric having a lever-handle T When the gate is closed, the link may be swung to enter the nose above the eccentric, and the eccentric then being rocked by means of the handle will at the same time draw the link in under the nose and crowd the latter, and thereby the gate, up against the packing. The movement of the handle for this purpose being from a horizontal down to a vertical position will render it secure at the latter position.

With certain sorts of slimes the deposit formed upon the cell by exhaustion of the liquid, as described, from within may have a tendency to crack or may be without cracking quite porous, so that when the supply of slimes is cut off, the exhaustion continuing and lowering the level of the liquid in the tank, the air will enter so easily through the deposit as to partially defeat the action of the suction in exhausting the tank to the bottom, and some slimes may be of such quality that they will not be retained after the liquid. is withdrawn from the exterior, but will fall off in cakes. In such cases when the supply of slimes is cut off a corresponding supply of solvent liquor will be admitted at the bottom through the pipes provided for that purpose, and thus the liquid will be maintained in the tank at the full level, becoming gradually deprived of the solid matter by deposit, so that it will eventually consist only of the solvent liquor, as would be the case if the slime-bearing liquor had been first exhausted and the other liquor substituted. In like manner after drawing the solvent liquor through the slimes for a sufiicient time to complete the process of dissolving out the metal values the liquid-supply will be changed to clear water while the tank is still full, and the suction being continued the liquid will gradually change from solvent to pure water, and then being continued long enough to complete the washing-,the supply being wholly cut off, the suction will be continued until the tank is exhausted, and if the deposit tends to break away and fall in this process no damage will be done, because this will be only an anticipation of the next step, which will consist in freeing it by the means described.

I claim 1. An apparatus for the treatment of oreslimes consisting of a filtering-cell having its length and breadth respectively horizontal and vertical and its thickness small relatively to the other dimensions; a tank in which such cell is suspended and which accommodates the same with relatively small space at opposite sides; suction-pipes intruded into the cell from the top, terminating open near the bottom;

means for producing suction through such pipes and means for supplying the slimebearing liquor to the tank and for aerating the same from the bottom.

2. An apparatus for the treatment of slimes consisting of a tank or vat whose width is small relatively to its depth and length; pipes extending longitudinally in the lateral wall of such tank near the bottom, perforated at their lower sides for discharge of air into the tank; means for supplying to the tank the material to be filtered; a filtering-cell suspended in the tank out of contact with its sides, and means for producing suction from within the cell to draw the liquor through its filtering-walls and discharge the same.

3. In an apparatus for the treatment of slimes consisting of a vertical tank having its thickness small relatively to its height and length, and a similarly-proportioned filteringcell suspended therein out of contact with its sides and bottom, the bottom of such tank being hinged to the body, and means for opening and closing and securing the same.

4:. An apparatus for the treatment of slimes comprising a tank whose width is small relatively to its length and height; a filteringcell similarly proportioned suspended within the tank out of contact with its sides and bottom; pipes extended along the sides of the filtering-cell at the upper end, having a multiplicity of discharges directed inward and downward for discharging flushing jets against the lateral walls of the cell; means for supplying to the tank liquor to be treated; means for sucking the liquid therefrom through the filtering-walls into the cells and conducting the same away, and means at the bottom of the tank for opening the same to permit discharge of the deposits flushed from the cell-walls.

In testimony whereof I have hereunto set my hand, in the presence of two witnesses, this 20th day of April, 1904:.

GUSTAVUS A. DUNCAN.

Witnesses:

I. B. EMrsoN, ROBERT C.HAYEs. 

